Vibration tolerant electronic assembly and related methods

ABSTRACT

A vibration tolerant electronic assembly may include a base and a first isolation stage including a first frame, at least one first linear bearing coupling the first frame to the base to constrain movement of the first frame along a first coordinate axis, and at least one first damper for damping movement of the first frame. A second similar isolation stage may be coupled to the first isolation stage, and a third similar isolation stage may be coupled to the second isolation stage. Furthermore, an electronic device may be coupled to the third isolation stage. The electronic assembly provides resistance to disturbance of the electronic device by vibration in one or more of three coordinate axis.

FIELD OF THE INVENTION

The present invention relates to the field of electronic devices, andmore particularly, to assemblies and methods for reducing vibrationthereof.

BACKGROUND OF THE INVENTION

Computers have become commonplace in a great number of applications.Depending upon the data storage and retrieval requirements of aparticular application, a computer will typically be configured with acertain combination of memory devices. This is because each particularmemory device has particular advantages and disadvantages in terms ofcost, speed, and storage capacity.

For example, memory such as cache memory has very fast read and writetimes, but it is typically one of the most costly types of memories andis often impractical to use on a large scale. On the other hand,writeable disk drives, such as magnetic hard disk drives or opticaldrives, are much less costly and provide a very large storage capacity,but generally have slower data transfer rates. Additionally, hard diskdrives can store data indefinitely even after power is no longersupplied. In between cache memory and disk drives is solid state memory,which is not as fast as cache memory but is less expensive. Further,solid state memory is faster than hard disk drives but stillsignificantly more expensive. Thus, solid state memory is simply not yetpractical for very large storage requirements where several Gigabytes oreven Terabytes of memory are needed.

Yet, to read or write data to a hard disk drive or optical drive, forexample, a read/write head has to be aligned with the disk while it ismoving to correctly transfer data to and from the disk. As a result,disk drives typically are susceptible to read and write errors caused bymovement or vibration. That is, the read/write head may be jarred out ofalignment with the spinning disk causing data transfer errors to occur.Even worse, such vibrations may cause damage to the moving components ofthe disk drive. This is because disk drives are typically quitesensitive to rotational motion and high G forces at high frequencies.While semiconductor memories such as solid state memories generally arenot prone to such vibration damage, as noted above, because of cost itmay not be economically feasible to use such memories in high stressenvironments where movement or vibration is likely if large data storagecapacities are required.

As a result, attempts have been made to reduce the effects of shock andvibration on disk drives so that they will be less prone to errors ordamage from movement or vibrations. One prior art example is disclosedin U.S. Pat. No. 6,097,608 to Berberich et al. entitled “Disk DriveVibration Isolation Using Diaphragm Isolators.” The patent discloses adiaphragm isolator frame for supporting a disk drive in a rack or otherenclosure while providing isolation from undesirable vibrations fromother disk drives, components mounted in the enclosure, or from theenvironment. The diaphragm isolator frame includes a pair of side railshaving diaphragm isolators formed of thinned portions of the side rails.Each diaphragm has a centrally located press-pin for supporting the diskdrive. Further, the thickness and diameter of the diaphragms may bechosen to provide vibration isolation at a desired frequency.

While such prior art devices may provide some vibration isolation, theystill may not be suitable for high stress environments where largeamounts of movement or vibration are commonplace, such as in certainmobile applications. For example, computers aboard planes, groundvehicles, etc. may be subject to rather violent shaking that may cause adisk drive mounted according to the prior art to fail or be damagedduring writing and/or reading operations. Nonetheless, with the everincreasing advancements in technology, computers with ever higher memorystorage capacities are needed that can accommodate such data intensivetechnologies as well as the rigors of high stress environments.

SUMMARY OF THE INVENTION

In view of the foregoing background, it is therefore an object of thepresent invention to provide a vibration tolerant electronic assemblyand related methods.

This and other objects, features, and advantages in accordance with thepresent invention are provided by a vibration tolerant electronicassembly including a base and a first isolation stage including a firstframe, at least one first linear bearing coupling the first frame to thebase to constrain movement of the first frame along a first coordinateaxis, and at least one first damper for damping movement of the firstframe along the first coordinate axis. Additionally, the vibrationtolerant electronic assembly may include a second isolation stageincluding a second frame, at least one second linear bearing couplingthe second frame to the first frame to constrain movement of the secondframe along a second coordinate axis, and at least one second damper fordamping movement of the second frame along the second coordinate axis.Furthermore, a third isolation stage may include a third frame, at leastone third linear bearing coupling the third frame to the second frame toconstrain movement of the third frame along a third coordinate axis, andat least one third damper for damping movement of the third frame alongthe third coordinate axis. The vibration tolerant electronic assemblymay also include an electronic device coupled to the third frame.

More particularly, the at least one first damper, the at least onesecond damper, and the at least one third damper may each include atleast one spring and/or at least one friction surface. The vibrationtolerant electronic assembly may further include at least one firstelastomeric coupler coupling the first and second frames together, andat least one second elastomeric coupler coupling the second and thirdframes together. At least one elastomeric coupler may also be includedfor coupling the electronic device to the third frame. The at least onefirst linear bearing, the at least one second linear bearing, and the atleast one third linear bearing may each include a pair of parallelspaced apart linear bearings, for example.

Further, the electronic device may be a magnetic disk data storagedrive, for example. Additionally, the vibration tolerant electronicassembly may further include a holder carried by the third frame uponwhich the electronic device is mounted, and a cover coupled to theholder for hermetically sealing the electronic device. The first frame,the second frame, and the third frame each may include metal, forexample, and the first isolation stage, the second isolation stage, andthe third isolation stage may have different resonant frequencies.

Another aspect of the invention relates to a vibration reduction systemfor an electronic device which may include a base and a first isolationstage including a first frame, at least one first linear bearingcoupling the first frame to the base to constrain movement of the firstframe along a first coordinate axis, and at least one first damper fordamping movement of the first frame along the first coordinate axis. Thevibration reduction system may also include a second isolation stageincluding a second frame, at least one second linear bearing couplingthe second frame to the first frame to constrain movement of the secondframe along a second coordinate axis, and at least one second damper fordamping movement of the second frame along the second coordinate axis.Further, a third isolation stage may be included to be coupled to theelectronic device. The third isolation stage may include a third frame,at least one third linear bearing coupling the third frame to the secondframe to constrain movement of the third frame along a third coordinateaxis, and at least one third damper for damping movement of the thirdframe along the third coordinate axis.

Considered in other terms, the vibration reduction system may include aplurality of isolation stages coupled to one another, where at least oneisolation stage includes a frame and at least one linear bearingcoupling the at least one isolation stage to an adjacent isolation stageto constrain movement of the frame along a coordinate axis. The at leastone isolation stage may further include at least one damper for dampingmovement of the frame along the coordinate axis.

A method aspect of the invention is for reducing vibration of anelectronic device and may include coupling a first frame to a base withat least one first linear bearing to constrain movement of the firstframe along a first coordinate axis and damping movement of the firstframe along the first coordinate axis with at least one first damper.The method may further include coupling a second frame to the firstframe with at least one second linear bearing to constrain movement ofthe second frame along a second coordinate axis and damping movement ofthe second frame along the second coordinate axis with at least onesecond damper. Furthermore, a third frame may be coupled to the secondframe with at least one third linear bearing to constrain movement ofthe third frame along a third coordinate axis, and movement of the thirdframe may be dampened along the third coordinate axis with at least onethird damper. Additionally, the electronic device may be coupled to thethird frame.

Considered in other terms, the method aspect may include coupling aplurality of isolation stages to one another, where at least oneisolation stage includes a frame and at least one linear bearing forcoupling the at least one isolation stage to an adjacent isolation stageand constraining movement of the frame along a coordinate axis. Themethod may also include damping movement of the frame along thecoordinate axis using at least one damper.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is perspective view of a vibration tolerant electronic assemblyaccording to the present invention.

FIG. 2 is an exploded view of the vibration tolerant electronic assemblyof FIG. 1.

FIG. 3 is a graph illustrating a vibration PSD curve for a disk drivemounted in a prior art vibration isolation assembly.

FIG. 4 is a graph illustrating a vibration PSD curve for a disk drivemounted in the vibration tolerant electronic assembly of the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described more fully hereinafter withreference to the accompanying drawings, in which preferred embodimentsof the invention are shown. This invention may, however, be embodied inmany different forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art. Likenumbers refer to like elements throughout.

Turning now to FIGS. 1 and 2, a vibration tolerant electronic assembly10 according to the present invention illustratively includes a base 11and a first isolation stage 12. The first isolation stage 12 includes afirst frame 13, which may include metal or other suitable materials suchas a rigid plastic, for example. Additionally, the first isolation stage12 also includes at least one first linear bearing 14 (e.g., liner ballbearings) coupling the first frame 13 to the base 11 via a mountingplate 19. Of course, the mounting plate 19 may be omitted in certainembodiments. A pair of parallel spaced apart first linear bearings 14 a,14 b are used in the illustrated embodiment, though other numbers oflinear bearings may be used in accordance with the present invention.

The linear bearings 14 a, 14 b constrain movement of the first frame 13along a first coordinate axis (i.e., the x axis in FIG. 2). That is, thelinear bearings 14 a, 14 b provide structural supports which constrainrotation of an electronic device 15 of the assembly 10, which will bediscussed further below. Furthermore, the first isolation stage 12 alsoincludes at least one first damper for damping movement of the firstframe 13 along the x axis. For example, the first damper may include atleast one spring 16. In the illustrated embodiment, only one spring 16is visible, but a second spring is used to provide biasing in bothdirections along the x axis, as will be appreciated by those of skill inthe art. The springs 16 are coupled between the first frame 13 and amounting fixture 17, which, in turn, is coupled to the mounting plate19.

Moreover, the at least one first damper may also include frictionsurfaces or plates 18 a, 18 b. The friction plates 18 a, 18 b may bemade of plastic or other suitable materials, for example, and are usedto cause friction between the mounting fixture 17 and the first frame 13when the first frame travels back and forth along the x axis. Thefriction plates may be mounted on either the first frame 13 or themounting fixture 17. The springs 16 and friction plates 18 a, 18 b alsoreduce the resonant amplification of movement of the first frame 13, aswill be appreciated by those of skill in the art.

Similarly, the illustrated vibration tolerant electronic assembly 10also includes a second isolation stage 20 similar to the first isolationstage 12. That is, the second isolation stage 20 includes a secondframe, which in turn includes a second lower subframe 21 and a secondupper subframe 31. The second lower subframe 21 includes a pair ofparallel spaced apart second linear bearings 22 a, 22 b coupling thesecond lower subframe to the first frame 13. The second linear bearings22 a, 22 b constrain movement of the second frame along a secondcoordinate axis (i.e., the y axis in FIG. 2). Again, other numbers oflinear bearings may also be used.

Furthermore, the second isolation stage 20 includes at least one seconddamper for damping movement of the second frame along the y axis, whichagain may include a pair of springs 23 a, 23 b and friction plates 24 a,24 b. Additionally, isolators or couplers 25, such as grommets or bodiesmade from an elastomeric material, for example, may optionally be usedto couple the first frame 13 and the second lower subframe 21 togetherand provide additional damping, particularly rotational damping betweenthe two stages.

Thus, when the elastomeric couplers 25 and the second lower subframe 21are used, the vibration tolerant electronic assembly 10 will besemi-rigid, i.e., a small amount of pivoting will take place between thefirst frame 13 and second upper subframe 31, which may be advantageousin certain applications. Of course, those of skill in the art willappreciate that other more rigid connectors may be used to substantiallyeliminate pivoting between the first frame 13 and the second uppersubframe 31 to provide a more rigid embodiment of the vibration tolerantelectronic assembly 10.

A third isolation stage 30, similar to the first isolation stage 12 andthe second isolation stage 20, also includes a third frame. In theillustrated embodiment, the third frame includes a third outer subframeportion 32 and a pair of third inner subframe portions 39 a, 39 b. Thethird inner subframes 39 a, 39 b each carry respective linear bearings33 a, 33 b which couple the third inner subframes to the third outersubframe 32 to constrain movement of the third inner subframes along athird coordinate axis (i.e., the z axis in FIG. 2). Further, the thirdinner subframes 39 a, 39 b also include at least one third damper whichagain dampens movement of the third frame 30 along the z axis and mayinclude springs 34 a, 34 b and friction plates 35 a, 35 b similar tothose described above. Both the second and third frames may be made ofsimilar materials as the first frame 13.

As may best be seen in FIG. 1, the third inner subframes 39 a, 39 b fitinside the third outer subframe 32 and down over the top and sides ofthe second upper subframe 31 and first frame 13. This is made possibleby the second upper subframe 31 which has dimensions in the x and ydirections that are preferably larger than that of the second lowersubframe 21. Additionally, opposing ends 36 of the second upper subframe31 are also formed so that the linear bearings 33 a, 33 b are positionedadjacent the sides of the second lower subframe 21. Of course, in otherembodiments the various isolation stages may be stacked on top of oneanother or otherwise arranged, if desired, as will be appreciated bythose of skill in the art. Once again, elastomeric couplers 38 may beused to couple the second upper subframe 31 to the third outer subframe32.

Additionally, the vibration tolerant electronic assembly 10 may furtherinclude a holder 40 carried by the third inner subframes 39 a, 39 b andupon which the electronic device 15 is mounted. The present invention isparticularly well suited for use with hard disk drives (e.g., magneticand optical disk drives), such as that illustratively shown in FIG. 2,for example. That is, the enhanced vibration damping resulting from thestructure of the present invention allows both reading and writing to beperformed on hard disk drives in high stress environments, as will bediscussed further in the example given below. Of course, the presentinvention may be used with numerous other electronic devices wherevibration damping is desired.

A cover 41 may be coupled to the holder 40 to not only provide physicalprotection for the electronic device 15 but also for hermeticallysealing the electronic device between the cover and the holder, ifdesired. The cover 41 and holder 40 may be made of similar materials asthe first frame 13. Further, one or more elastomeric couplers 37 mayalso be included for coupling the holder 40 to the third inner subframes39 a, 39 b to provide still further vibration damping. Again, rigidcouplers may be used in some embodiments, if desired.

As a result of the above construction, the vibration tolerant electronicassembly 10 is fairly compact and requires little if any additionalmounting space than would otherwise be required with prior art isolationsystems. Further, the illustrated embodiment also advantageously placesall of the elastomeric couplers 25, 37, 38 at about the same height sothat the various pivot points associated therewith are substantially inthe same plane. This aspect, in addition to the use of multiple dampersin each of the first isolation stage 12, the second isolation stage 20,and the third isolation stage 30 significantly compound vibrationdampening. Further, the present invention may be used over a wideoperating frequency range of up to about 2000 Hz or higher.

Additionally, by adjusting the properties of the various springs,friction plates, and elastomeric couplers, as well as the rigidity andmass of the frames, for example, respective resonant frequencies of thefirst isolation stage 12, the second isolation stage 20, and the thirdisolation stage 30 may advantageously be set to not be equal. Of course,other suitable damping devices known to those of skill in the art mayalso be used. Preferably, these resonant frequencies are set as farapart as possible. Also, in those embodiments where elastomeric couplersare used to provide pivoting between the various frames, it may also bedesirable to space the pivot points out as far as possible, as will beappreciated by those skilled in the art.

EXAMPLE

By way of comparison, FIGS. 3 and 4 are graphs illustrating vibrationpower spectrum density (PSD) output curves for a magnetic disk drive ina prior art isolation assembly (RMS=1.299 g) and in the vibrationtolerant electronic assembly 10 made according to the present invention(RMS=1.007 g), respectively. The prior art assembly tested included aframe, a holder for the magnetic disk drive positioned within the frame,and elastomeric couplers coupling the holder to the frame. A Travelstarmodel disk drive manufactured by the IBM Corporation was used in bothassemblies.

Respective inputs 50, 52 were provided to the disk drives in the priorart assembly and the vibration tolerant electronic assembly 10 accordingto the present invention, and the G forces experienced by the diskdrives are illustrated in the respective vibration PSD output curves 51,53. As will be appreciated by those of skill in the art upon comparisonof the output curves 51, 53, approximately 20 to 30 dB in isolationimprovement was achieved according to the present invention.

Another aspect of the invention relates to a vibration reduction systemfor an electronic device 15. The vibration reduction system includes abase 11 and a first isolation stage 12 including a first frame 13, atleast one first linear bearing 14 coupling the first frame to the base11 to constrain movement of the first frame along a first coordinateaxis, and at least one first damper (e.g., the springs 16 and/orfriction plates 18 a, 18 b) for damping movement of the first framealong the first coordinate axis, as previously described above. Thevibration reduction system may also include a second isolation stage 20and a third isolation stage 30, again as previously described above. Theelectronic device 15 is to be coupled to the third inner subframes 39 a,39 b of the third isolation stage 30 via the holder 40, for example.

A method aspect of the invention is for reducing vibration of anelectronic device 15 and may include coupling a first frame 13 to a base11 with at least one first linear bearing 14 to constrain movement ofthe first frame along a first coordinate axis, as previously describedabove. Furthermore, movement of the first frame may be dampened alongthe first coordinate axis using the springs 16 and/or the frictionplates 18 a, 18 b. The method may further include coupling a secondupper subframe 31 of a second frame to the first frame 13 with linearbearings 22 a, 22 b to constrain movement of the second frame along asecond coordinate axis.

Again, damping of movement of the second frame along the secondcoordinate axis may be performed using the springs 23 a, 23 b and/or thefriction plates 24 a, 24 b. Furthermore, third inner subframes 39 a, 39b of a third frame may be coupled to the second upper subframe 31 withthird linear bearings 33 a, 33 b to constrain movement of the thirdframe along a third coordinate axis, and movement of the third innersubframes 39 a, 39 b may be dampened along the third axis by the springs34 a, 34 b and friction plates 35 a, 35 b. Additionally, the electronicdevice 15 may be coupled to the third inner subframes 39 a, 39 b via theholder 40. The remaining aspects of the method may be as previouslydescribed above.

Many modifications and other embodiments of the invention will come tothe mind of one skilled in the art having the benefit of the teachingspresented in the foregoing descriptions and the associated drawings.Therefore, it is understood that the invention is not to be limited tothe specific embodiments disclosed, and that modifications andembodiments are intended to be included within the scope of the appendedclaims.

That which is claimed is:
 1. A vibration tolerant electronic assemblycomprising: a base; a first isolation stage comprising a first frame, atleast one first linear bearing coupling said first frame to said base toconstrain movement of said first frame along a first coordinate axis,and at least one first damper for damping movement of said first framealong the first coordinate axis; a second isolation stage comprising asecond frame, at least one second linear bearing coupling said secondframe to said first frame to constrain movement of said second framealong a second coordinate axis, and at least one second damper fordamping movement of said second frame along the second coordinate axis;a third isolation stage comprising a third frame, at least one thirdlinear bearing coupling said third frame to said second frame toconstrain movement of said third frame along a third coordinate axis,and at least one third damper for damping movement of said third framealong the third coordinate axis; and an electronic device coupled tosaid third frame.
 2. The vibration tolerant electronic assembly of claim1 wherein said at least one first damper, said at least one seconddamper, and said at least one third damper each comprises at least onespring.
 3. The vibration tolerant electronic assembly of claim 1 whereinsaid at least one first damper, said at least one second damper, andsaid at least one third damper each comprises at least one frictionsurface.
 4. The vibration tolerant electronic assembly of claim 1further comprising at least one first elastomeric coupler coupling saidfirst and second frames together, and at least one second elastomericcoupler coupling said second and third frames together.
 5. The vibrationtolerant electronic assembly of claim 1 further comprising at least oneelastomeric coupler coupling said electronic device to said third frame.6. The vibration tolerant electronic assembly of claim 1 wherein saidfirst isolation stage, said second isolation stage, and said thirdisolation stage have different resonant frequencies.
 7. The vibrationtolerant electronic assembly of claim 1 wherein said at least one firstlinear bearing, said at least one second linear bearing, and said atleast one third linear bearing each comprises a pair of parallel spacedapart linear bearings.
 8. The vibration tolerant electronic assembly ofclaim 1 wherein said electronic device comprises a magnetic disk datastorage drive.
 9. The vibration tolerant electronic assembly of claim 1further comprising: a holder carried by said third frame upon which saidelectronic device is mounted; and a cover coupled to said holder forhermetically sealing said electronic device.
 10. The vibration tolerantelectronic assembly of claim 1 wherein said first frame, said secondframe, and said third frame each comprises metal.
 11. A vibrationtolerant electronic assembly comprising: a base; a first isolation stagecomprising a first frame, at least one first linear bearing couplingsaid first frame to said base to constrain movement of said first framealong a first coordinate axis, and at least one first spring for dampingmovement of said first frame along the first coordinate axis; a secondisolation stage comprising a second frame, at least one second linearbearing coupling said second frame to said first frame to constrainmovement of said second frame along a second coordinate axis, and atleast one second spring for damping movement of said second frame alongthe second coordinate axis; a third isolation stage comprising a thirdframe, at least one third linear bearing coupling said third frame tosaid second frame to constrain movement of said third frame along athird coordinate axis, and at least one third spring for dampingmovement of said third frame along the third coordinate axis; and amagnetic disk data storage drive coupled to said third frame.
 12. Thevibration tolerant electronic assembly of claim 11 wherein said firstisolation stage, said second isolation stage, and said third isolationstage each further comprises at least one friction surface for furtherdamping respective movements of said first frame, said second frame, andsaid third frame.
 13. The vibration tolerant electronic assembly ofclaim 11 further comprising at least one first elastomeric couplercoupling said first and second frames together, and at least one secondelastomeric coupler coupling said second and third frames together. 14.The vibration tolerant electronic assembly of claim 11 furthercomprising at least one elastomeric coupler coupling said disk drive tosaid third frame.
 15. The vibration tolerant electronic assembly ofclaim 11 wherein said first isolation stage, said second isolationstage, and said third isolation stage have different resonantfrequencies.
 16. The vibration tolerant electronic assembly of claim 11wherein said at least one first linear bearing, said at least one secondlinear bearing, and said at least one third linear bearing eachcomprises a pair of parallel spaced apart linear bearings.
 17. Thevibration tolerant electronic assembly of claim 11 further comprising: aholder carried by said third frame upon which said electronic device ismounted; and a cover coupled to said holder for hermetically sealingsaid electronic device.
 18. The vibration tolerant electronic assemblyof claim 11 wherein said first frame, said second frame, and said thirdframe each comprises metal.
 19. A vibration reduction system for anelectronic device comprising: a base; a first isolation stage comprisinga first frame, at least one first linear bearing coupling said firstframe to said base to constrain movement of said first frame along afirst coordinate axis, and at least one first damper for dampingmovement of said first frame along said first coordinate axis; a secondisolation stage comprising a second frame, at least one second linearbearing coupling said second frame to said first frame to constrainmovement of said second frame along a second coordinate axis, and atleast one second damper for damping movement of said second frame alongsaid second coordinate axis; and a third isolation stage to be coupledto the electronic device, said third isolation stage comprising a thirdframe, at least one third linear bearing coupling said third frame tosaid second frame to constrain movement of said third frame along athird coordinate axis, and at least one third damper for dampingmovement of said third frame along said third coordinate axis.
 20. Thevibration reduction system of claim 19 wherein said at least one firstdamper, said at least one second damper, and said at least one thirddamper each comprises at least one spring.
 21. The vibration reductionsystem of claim 19 wherein said at least one first damper, said at leastone second damper, and said at least one third damper each comprises atleast one friction surface.
 22. The vibration reduction system of claim19 further comprising at least one first elastomeric coupler couplingsaid first and second frames together, and at least one secondelastomeric coupler coupling said second and third frames together. 23.The vibration reduction system of claim 19 further comprising at leastone elastomeric coupler coupling said electronic device to said thirdframe.
 24. The vibration reduction system of claim 19 wherein said firstisolation stage, said second isolation stage, and said third isolationstage have different resonant frequencies.
 25. The vibration reductionsystem of claim 19 wherein said at least one first linear bearing, saidat least one second linear bearing, and said at least one third linearbearing each comprises a pair of parallel spaced apart linear bearings.26. The vibration reduction system of claim 19 further comprising: aholder carried by said third frame upon which said electronic device ismounted; and a cover coupled to said holder for hermetically sealingsaid electronic device.
 27. The vibration reduction system of claim 19wherein said first frame, said second frame, and said third frame eachcomprises metal.
 28. A method for reducing vibration of an electronicdevice comprising: coupling a first frame to a base with at least onefirst linear bearing to constrain movement of the first frame along afirst coordinate axis and damping movement of the first frame along thefirst coordinate axis with at least one first damper; coupling a secondframe to the first frame with at least one second linear bearing toconstrain movement of the second frame along a second coordinate axisand damping movement of the second frame along the second coordinateaxis with at least one second damper; coupling a third frame to thesecond frame with at least one third linear bearing to constrainmovement of the third frame along a third coordinate axis and dampingmovement of the third frame along the third coordinate axis with atleast one third damper; and coupling the electronic device to the thirdframe.
 29. The method of claim 28 wherein the at least one first damper,the at least one second damper, and the at least one third damper eachcomprises at least one spring.
 30. The method of claim 28 wherein the atleast one first damper, the at least one second damper, and the at leastone third damper each comprises at least one friction surface.
 31. Themethod of claim 28 wherein coupling the second frame to the first framefurther comprises coupling the first and second frames together using atleast one first elastomeric coupler, and wherein coupling the thirdframes to the second frame further comprises coupling the second andthird frames together using at least one second elastomeric coupler. 32.The method of claim 28 wherein coupling the electronic device to thethird frame comprises coupling the electronic device to the third frameusing at least one elastomeric coupler.
 33. The method of claim 28wherein the first isolation stage, the second isolation stage, and thethird isolation stage have different resonant frequencies.
 34. Themethod of claim 28 wherein the at least one first linear bearing, the atleast one second linear bearing, and the at least one third linearbearing each comprises a pair of parallel spaced apart linear bearings.